This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Exocrine pancreatic insufficiency EPI is a syndrome characterized by poor absorption of fats, proteins and to a lesser extent, carbohydrates, which manifests in patients with chronic pancreatitis CP. 1 Zentase is a new porcine-derived pancreatic enzyme replacement product developed for the treatment of malabsorption associated with EPI. This study has been designed to assess the efficacy of a high and low dose of Zentase compared to placebo in the treatment of the signs and symptoms of malabsorption in CP patients with EPI. A comparison will be made of the mean improvement in the Coefficient of Fat Absorption CFA after administration of the two different doses of Zentase vs. placebo. Each subject will begin the study on placebo then be randomized to one of the two treatment phases. Each phase of the study requires the subject to fill in a diary containing data on study drug consumption, diet and clinical signs and symptoms, other drugs taken and any adverse events. Subjects will come to the General Clinical Research Center for a total of 3 times to have a quantitative fecal fat assessment which will include a 100g fat diet with a 72 hour quantitative fecal fat collection and analysis.